RC Polymer: A specific Nano Pro-Tech butadiene rubber that is specifically designed to react with silica, improving tread flexibility to provide enhanced wet traction and long wear life

Nano Pro-Tech: Is a Bridgestone proprietary technology that controls the interaction between polymer, filler materials (carbon black, silica) and other rubber chemicals at the molecular level

Tire Construction:

Mono-Spiral Belt construction: A continuous single strand of cord is wrapped around the circumference and serves as a belt of a tire, eliminating overlapping of belts, seams, and joints

Mono-Spiral Belt construction makes the tire lighter than conventional multi cross belt construction, has more stability since it minimizes heat generation inside the tire, and gives high shock absorption

High Tensile Super Penetrated Cord (HTSPC): Features a 1X5 filament, rubber insulated steel Mono-Spiral Belt allowing more flexibility than other types of the steel used by competitors, reduces heat generation, and provides stability without deteriorating shock absorption

I bought this as a tire package deal. I didn't need the front now but couldn't pass up the deal. From my past experience with this brand and tire I have yet to find anything wrong about the tire. Great craftmenship good quality and all around good tire.